It is proposed to conduct the first phase of a three-part prospective study on a group of subjects considered to be at high risk for the development of alcoholism. This American-Danish research team has previously reported that alcoholism may in part be genetically determined. This was found both with adopted and nonadopted sons of Danish alcoholic parents. Interestingly, a genetic factor was not observed in the adopted daughters of alcoholic parents. The present study proposes to compare 200 sons of alcoholic parents and 100 matched controls in order to discern the experiential factors which might correlate with alcoholism in later life. The study will utilize a unique cohort of subjects which had been studied extensively 16-18 years ago in a prospective obstetrical study. Hence detailed prenatal and perinatal history already exists both for the subjects and their families. Out of this cohort, 250 boys and 226 girls had been identified to have an alcoholic parent. Based on the previous work of this research team, the male children would constitute a high-risk group since it is estimated that 20-25% of them will develop alcoholism between the ages of 20 and 30. This cohort is now at the age of 16-18, just preceding the period that problem drinking will become evident. Hence there is a sense of urgency to obtain the necessary studies on them before they enter the period of unrestrained exposure. It is proposed that the mothers (or guardian) and the subjects be interviewed according to a standardized protocol with regard to social, developmental, and medical history, and the subjects be evaluated by a formal psychiatric examination and by a battery of psychological and neuropsychological tests. Additionally, school, health, criminal and welfare records will be scrutinized and history of drugs and alcohol use will be sought. A physical neurological examination will be performed. It is anticipated that the same group of subjects will be similarly studied at about age 22 and at age 28, and together, the data will be analyzed to identify factors which might correlate with or be predictive of alcoholism.